Description
chair: Agnieszka Janiuk, Julian Sitarek
Supermassive black hole mergers are one of the most dramatic phenomena in the Universe. For a few hours, they can emit as much power in gravitational waves as all the stars in the Universe produce in light. Moreover, they are an important element in determining the mass distribution of the entire population of supermassive black holes. However, none has yet been caught in the act, in large...
Neutron stars are an extraordinary laboratory in which to study matter in extreme conditions of density, magnetic energy and gravity. Modelling the interior of these objects requires an understanding of high density physics and phenomena such as superfluidity, which are well known in laboratory settings, but must now be understood in a strong gravity, relativistic setting. This issue is...
GRBs are panchromatic events, very attractive sources of study from very high energy (GeV and TeV) to very low frequency until radio. This gives the unique opportunity to study their emission mechanism in multiwavelength. Relevant cases are the GRB 190114C observed by the Major Atmospheric Gamma Imaging Cherenkov telescopes detected above 0.2 TeV, recording the most energetic photons ever...
The talk will cover the recent numerical investigation of a system composed of a Supermassive Black Hole Binary (SMBHB) and a non-self-gravitating, thin, locally isothermal, viscous disk.
The evolution of such a configuration is relevant not only for the expected gravitational-wave signal, but also for electromagnetic searches for SMBHB candidates. In 2-dimensional, Newtonian, numerical...
Recently, Peissker, Eckart, Zajacek et al. (2020) have reported the discovery of six faint stars in the innermost cluster of the Galaxy, so-called S cluster. These stars, S4711-S4715 and S62, can be monitored in the near-infrared K-band using both photometry and spectroscopy. Their elliptical orbits around the supermassive black hole (Sgr A*) break several records. S4711 with the orbital...
Accretion disks in High mass X-ray binaries (HMXB's) are mostly fed by the stellar wind from there companion star. These winds also affect the observed X-ray spectra arising from the hot coronal flow.
Cygnus X-1 and its companion star, HDE-226868 is one of such HMXBs. It is one of the brightest X-ray sources observed and shows the X-ray intensity variations in both the soft and hard X-rays....
Force-free electrodynamics is a non-linear regime of Maxwell's equations capable to provide the minimal non-trivial level of description for pulsar and black hole magnetospheres. For this system to be hyperbolic it is necessary that the field is magnetically dominated, F^2=B^2-E^2>0. Despite its crucial role in explaining energy and angular momentum extraction from slowly spinning black holes...
